Tomlinson agreed, saying he finds it ‘absolutely infuriating’ how firms have been treated, including suppliers to his own businesses.

His appearance follows his report, published last year, which claimed RBS pushes some small business customers into its ‘turnaround’ division, Global Restructuring Group, even though they are not in a desperate state.

Few escape this black hole, which means they are ‘put on a journey towards administration, receivership and liquidation’, it said.

RBS (down 2.7p at 341.2p) has asked the lawyers Clifford Chance to investigate Tomlinson’s claims.
The bank, which is 81p er cent-owned by the taxpayer, says many businesses re-emerge from the controversial GRG division, such as Thomas Cook and Samsonite.

A spokesman said: ‘The vast majority of businesses that have gone through GRG have had a positive outcome, either returned to the main bank, moved to another bank or paid their debt back with only a minority facing insolvency.

‘These are serious allegations that have done damage to RBS’s reputation, and the independent review by Clifford Chance we have commissioned will examine these.’